Spline joints and container having same

ABSTRACT

A container including a first panel with a first edge having a first protrusion with a first contoured profile with at least one projection, a second panel with a second edge having a second protrusion with a second contoured profile with at least one projection, and a spline with a first channel that defines a recess with an interior profile, and a second channel separate from the first channel that defines a recess with an interior profile. The first and second channels receive the first and second protrusions, respectively, such that the first contoured profile is complementary to a portion of the interior profile and the second contoured profile is complementary to a portion of the interior profile. The first and second panel include a mid-section extending from the first and second edges, respectively. The first and second edges have a greater thickness than the thickness of the mid-sections.

RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.16/852,646, filed Apr. 20, 2020, now U.S. Pat. No. 11,136,073, which isa continuation of U.S. application Ser. No. 15/962,341, filed Apr. 25,2018, now U.S. Pat. No. 10,625,790, the entire contents of both of whichare hereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to containers, and in particular, tojoints for connecting wall panels of containers.

BACKGROUND

Containers, for example commercial containers transported by trucks,commercial nautical vessels, trains, and the like include a set of wallsthat enclose the space of the container. The walls and connectionstherebetween are typically formed by assembling respective wall panelstogether forming a joint, often including additional splice plates, andthen fastening the joints with numerous fasteners such as screws orrivets.

SUMMARY

In one aspect, the invention provides a container defining a cargoreceiving interior defined by a plurality of panels. The containerincludes a first panel having a first edge. The first edge including afirst protrusion with a first contoured profile. The first contouredprofile includes at least one projection. The container also includes asecond panel with a second edge. The second edge includes a secondprotrusion with a second contoured profile. The contoured profileincludes at least one projection. The container further includes aspline having a first channel that defines a recess with an interiorprofile and a second channel separate from the first channel thatdefines a recess with an interior profile. The first channel receivesthe first protrusion of the first panel such that the first contouredprofile is complementary to a portion of the interior profile. Thesecond channel receives the second protrusion of the second panel suchthat the second contoured profile is complementary to a portion of theinterior profile. The first panel further includes a mid-sectionextending from the first edge and the second panel further includes amid-section extending from the second edge. The first edge has a greaterthickness than the thickness of the mid-section of the first panel andthe second edge has a greater thickness than the thickness of themid-section of the second panel.

In another aspect, the invention provides a container defining a cargoreceiving interior defined by a plurality of panels. The containerincluding a first contoured edge of a first panel, a second contourededge of a second panel, and a spline with a first channel that receivesthe first contoured edge and a second channel that receives the secondcontoured edge to form a spline joint securing the first and secondpanels together. The first and second channels are symmetrical withopenings in opposite directions. Each of the first and second contourededges includes a concavity containing an adhesive that bonds a surfaceof the respective first and second contoured edges with a surface ofrespective first and second channels of the spline.

In another aspect, the invention provides a method of assembling acontainer. The container defines a cargo receiving interior defined by aplurality of panels. The method includes providing a first panel with afirst contoured edge and a second panel with a second contoured edge.The first panel and the second panel are held fixed relative to eachother to define a space between the first and second contoured edges.The method also includes providing a spline with two symmetricalchannels that open in opposite directions and sliding the spline axiallyand simultaneously onto the first and second contoured edges and intothe space therebetween so that a first one of the two symmetricalchannels receives the first contoured edge and a second one of the twosymmetrical channels receives the second contoured edge to from a splinejoint securing the first panel to the second panel. The method furtherincludes, after the first and second panels are secured, applying anadhesive to a concavity on the first contoured edge to bond a surface ofthe first contoured edge with a surface of one of the two symmetricalchannels, and applying an adhesive to a concavity on the secondcontoured edge to bond a surface of the second contoured edge with asurface of the other of the two symmetrical channels after the first andsecond panels are secured.

In another aspect, the invention provides a container defining a cargoreceiving interior defined by a plurality of panels. The containerincludes a first panel having a first edge. The first edge including afirst protrusion with a first contoured profile. The first contouredprofile includes at least one projection. The container also includes asecond panel with a second edge. The second edge includes a secondprotrusion with a second contoured profile. The contoured profileincludes at least one projection. The container further includes aspline having a first channel that defines a recess with an interiorprofile and a second channel separate from the first channel thatdefines a recess with an interior profile. The first channel receivesthe first protrusion of the first panel such that the first contouredprofile is complementary to a portion of the interior profile. Thesecond channel receives the second protrusion of the second panel suchthat the second contoured profile is complementary to a portion of theinterior profile. Each of the first and second contoured profilesincludes a concavity containing an adhesive that bonds a surface of therespective first and second contoured profiles with a surface of theinterior profile of the respective first and second channels of thespline.

Other aspects of the invention will become apparent by consideration ofthe detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a first perspective view of a container.

FIG. 2 is a second perspective view of the container of FIG. 1 .

FIG. 3 is a perspective view of the container of FIG. 1 without walls.

FIG. 4 is a perspective view of a spline joint on the container of FIG.1

FIG. 5 is a perspective view of a spline according to one embodiment ofthe invention.

FIG. 6 is a top view of the spline of FIG. 5 .

FIG. 7 is a perspective view of a spline according to another embodimentof the invention.

FIG. 8 is a top view of the spline of FIG. 7 .

FIG. 9 is a perspective view of a spline according to another embodimentof the invention.

FIG. 10 is a top view of the spline of FIG. 9 .

FIG. 11 is a side view of the spline of FIG. 9 .

FIG. 12 is a perspective view of a wall panel of the container of FIG. 1.

FIG. 13 is a detail view of a side edge of the wall panel of FIG. 12according to one embodiment of the invention.

FIG. 14 is a detail view of a side edge of the wall panel of FIG. 12according to another embodiment of the invention.

FIG. 15 is a top view of the spline joint of FIG. 4 .

FIG. 16 is a top view of a spline joint according to another embodimentof the invention.

FIG. 17 is a top view of a spline joint according to another embodimentof the invention.

FIG. 18 is a top view of a spline joint according to another embodimentof the invention.

FIG. 19 is a top view of a spline joint according to another embodimentof the invention.

FIG. 20 is a top view of a spline joint according to another embodimentof the invention.

FIG. 21 is a top view of a spline joint according to another embodimentof the invention.

FIG. 22 is a top view of a spline joint according to another embodimentof the invention.

FIG. 23 is a perspective view of an interior of the container of FIG. 1.

DETAILED DESCRIPTION

Before any embodiments of the invention are explained in detail, it isto be understood that the invention is not limited in its application tothe details of construction and the arrangement of components set forthin the following description or illustrated in the accompanyingdrawings. The invention is capable of other embodiments and of beingpracticed or of being carried out in various ways. It should beunderstood that the description of specific embodiments is not intendedto limit the disclosure from covering all modifications, equivalents,and alternatives falling within the spirit and scope of the disclosure.Also, it is to be understood that the phraseology and terminology usedherein is for the purpose of description and should not be regarded aslimiting.

The term “laterally” or variations thereof refer to a sidewaysdirection. The terms “top,” “upper,” “bottom,” and “lower” are intendedto indicate directions when viewing the container when positioned foruse. The term “coupled” means connected to or engage with, whethereither directly or indirectly, for example with an intervening member,and does not require the engagement to be fixed or permanent, althoughengagement can be fixed or permanent. It should be understood that theuse of numerical terms “first,” “second,” “third,” etc. as used hereindoes not refer to any particular sequence or order of components; forexample, “first” and “second” portions may refer to any sequence of suchcomponents, and is not limited to the first and second components of aparticular configuration.

FIGS. 1 and 2 illustrate a container, embodied here as a trailer 10 forover-the-road use with a truck to transport large cargo volumes. Inother embodiments, the container may be a fixed storage construction, acargo container, a shipping container, a straight truck, or the like. Asshown, the trailer 10 is a semi-trailer configured for use with a roadtractor (i.e., in forming a so called 18-wheeler). Aspects of theinvention are not necessarily limited to such a trailer 10, and aspectsof the disclosure will be understood as also applying to other trailersand containers of various configurations. The trailer 10 includes achassis 14 having axles with multiple sets of wheels 18, althoughsimilar containers may be provided with alternate rolling chassisconfigurations or none at all. The trailer 10 defines a length L in alongitudinal or transport direction. The length L can be 53 feet in someconstructions, although the trailer 10 can be manufactured in otherlengths greater than or less than 53 feet. Perpendicular to thelongitudinal direction, the trailer 10 defines a width W and a height H.The width W cooperates with the length L to define a plan view footprintof the trailer 10, while the height H of the trailer 10 is measuredperpendicular to the footprint (i.e., perpendicular to the ground).Subtracting for wall thicknesses, the length L, the width W, and theheight H cooperate to define a cargo receiving interior 22 (FIG. 2 ) ofthe trailer 10.

The trailer 10 includes a first side defined by a first side wall 26, asecond side defined by a second side wall 30 opposite the first sidewall 26, a front defined by a front wall 34, and a rear 38. Wall panels42 may form walls that span the first side wall 26, second side wall 30,and front wall 34. Each of the first side wall 26, second side wall 30,and front wall 34 can be constructed of one or more wall panels 42.Further in some embodiments, a wall panel may wrap around a corner ofthe trailer and form parts of multiple walls (e.g., the front wall andone of the first and second side walls). All of the wall panels 42extend between a roof 46 of the trailer 10 and a floor 50 of the trailer10. Consecutive wall panels 42 can be joined together by a spline 54forming a joint (e.g., spline joint 58, FIG. 4 ) that extends parallelto the direction of the height H of the trailer 10 between the roof 46and floor 50 of the trailer 10. As shown in FIG. 2 , the rear 38 of thetrailer 10 includes at least one door panel 62 provided to selectivelyopen for accessing the interior 22 for loading and unloading.

As shown in FIG. 3 , the trailer 10 includes a frame 66 including, oneach side, a top rail 78 adjacent the roof 46, a bottom rail 82 adjacentthe floor 50, and support posts 84. The top rail 78 and the bottom rail82 extend parallel to the longitudinal or lengthwise direction of thetrailer 10. The support posts 84 are positioned perpendicular to thelongitudinal direction and spaced along the length L of the trailer 10.

With reference to FIGS. 5 and 6 , the spline 54 includes a first end 86,a second end 90 opposite the first end 86, and a length L1 between thefirst and second ends 86, 90. The length L1 of the spline 54 defines thelength of the spline joint 58. The spline 54 also includes a firstchannel 94 that defines a first recess 98 and a second channel 102 thatdefines a second recess 106. Each of the first and second channels 94,102 is formed as an open-channel or structure and the first and secondchannels 94, 102 forming the spline 54 can be integrally formed as asingle piece or separately formed and joined together. The first andsecond channels 94, 102 both have openings 110 to their respectiverecesses 98, 106 that open in opposite directions of one another. Thefirst and second channels 94, 102 are also symmetrical about an axis 114that extends through the center of the spline 54. Each of the first andsecond recesses 98, 106 includes a respective interior profile 118 thatspans the inside of their respective channels 94, 102. The interiorprofiles 118 are defined along four sides 122A-D that form a rectangulararrangement with adjacent sides 122A-D being perpendicular to oneanother. The two directly adjacent sides 122C of the respective firstand second channels 94, 102 cooperatively form a web 124 of the spline54 that extends between, on one end of the web 124, the sides 122Carranged toward the interior and, on the other end of the web 124, thesides 122D arranged toward the exterior. Although referred to herein asindividual sides, the two sides 122C are arranged in the illustratedconstruction to be coextensive, forming one side of the spline 54 as awhole, and the same may be said of the two sides 122D. For example, thespline 54 may be viewed as having a modified I-beam shape, where the web124 extends between the midsections of two parallel, spaced sides.

Each of the interior profiles 118 of the spline 54 includes a maleprojection 126 that extends from one side (e.g., the exterior side 122D)of the channel 94, 102 into the open space that otherwise forms thefemale recess 98, 106. As illustrated, each projection 126 extendsperpendicularly from the side 122D. In the case that the projections 126extend from the exterior sides 122D in both channels 94, 102, this meansthat the projections 126 extend in a direction toward the interior ofthe trailer 10. As shown in FIG. 6 , one side of each projection 126 isflat while another side (e.g., an opposite side) is curved. As shown,the two projections 126 of the spline 54 are arranged so that the twocurved sides are facing each other and the two flat sides are facingaway from each other. Although the interior profiles 118 are shown toinclude exactly one pair of mirror-image projections 126, one or both ofthe interior profiles 118 can alternately include more or fewerprojections 126. Further, the projections 126 are not mirror-images inother constructions, and each projection 126 can have any convenientnumber of flat and/or round sides. In further embodiments, each interiorprofile 118 may include more or less than the four sides as illustrated,and the sides of the interior profiles may differ in shape from thatshown.

FIGS. 7 and 8 illustrate a spline 130 according to another embodiment.The spline 130 is similar to the spline 54, with like features beingrepresented by like reference numerals. The spline 130 includes anadditional channel 134 (e.g., a central channel 134) that extends thelength L1 of the spline 130 at a position between the first and secondchannels 94,102. The central channel 134 can be positioned exactlycentrally within the spline 130, or offset therefrom. Although thecentral channel 134 has a regular, symmetrical shape, alternate shapesare optional. The central channel 134 is defined between the separate,spaced apart sides 122C of the first channel 94 and the second channel102. These two sides 122C form parallel webs that bound the centralchannel 134. The central channel 134 defines an interior 138 that isrectangular, notwithstanding the rounded corners, and is positionedbetween the first and second channels 94, 102.

FIGS. 9-11 , illustrate a spline 140 according to another embodiment.The spline 140 is similar to the splines 54, 130 with like featuresbeing represented by like reference numerals. The spline 140 includesthe central channel 134 and a plurality of slots 142 (e.g., logisticslots) that extend into the interior 138 of the central channel 134through an interior-facing wall 146 of the spline 140. The slots 142extend the entire length L1 of the spline 140 from the first end 86 tothe second end 90 of the spline 140. The slots 142 may take any numberof different shapes, including the simple elongate holes as illustrated.When a spline joint 58 including a spline 140 is assembled, the logisticslots 142 are exposed to the interior 22 of the trailer 10 so as toprovide attachment points for load separators or other restraints thatmay be secured to the interior 22 of the trailer 10.

Referring to FIG. 12 , some or all of the wall panels 42 of the trailer10 include a top edge 150, a bottom edge 154 opposite the top edge 150,a first side edge 158 (right), a second side edge 162 (left) oppositethe first side edge 158, and a mid-section 166 spanning between thefirst and second side edges 158, 162. In the illustrated embodiment, thefirst and second side edges 158, 162 extend the entire length of thewall panels 42 from the bottom edge 154 to the top edge 150. In otherembodiments, the first and second side edges 158, 162 only extend amajority portion of the length between the top and bottom edges 150,154. Referring now to FIG. 13 , the first and second side edges 158, 162of any respective wall panel 42 are oblong shaped and include aprotrusion 170 that extends towards the interior 22 of the trailer 10when the wall panel 42 is positioned for use. In other words, theprotrusion 170 is offset inwards from a plane P that is defined by aninterior surface of the wall panel 42 at a location (e.g., themid-section 166) along the wall panel 42 that is spaced away from theprotrusion 170. Each of the protrusions 170 on respective first andsecond side edges 158, 162 of the wall 42 include a contoured profile174. In other words, the contoured profiles 174 are irregularly shapedand not strictly defined by flat or straight ends. The contoured profile174 includes a projection 176 that extends towards the plane P (e.g.,extending toward the exterior when assembled for use). In theillustrated embodiment, the contoured profile 174 of the protrusion 170on the first side edge 158 of the wall panel 42 corresponds to theinterior profile 118 of the first channel 94 of the spline 54 and thecontoured profile 174 of the protrusion 170 on the second side edge 162of the wall panel 42 corresponds to the interior profile 118 of thesecond channel 102 of the spline 54. The protrusion 170 on the firstedge 158 of the wall 42 is complementary in shape to the first channel94, and the protrusion 170 on the second edge 162 of the wall panel 42is complementary in shape to the second channel 102 of the spline 54.The protrusions 170 are oversized with respect to the openings 110 ofthe channels 94, 102 of the spline 54 to preclude passage of the edges158, 162 of the wall panel 42 through the openings of the channels 94,102. Although in the illustrated embodiment, the contoured profiles 174are mirror-images of one another, each including a single projection176, the contoured profiles 174 are, in some constructions, differentfrom each other and either one or both may differ in shape from thatshown herein, e.g., the contoured profile 174 may include more or fewerprojections 176 or projections 176 of alternate shapes. It is noted herethat the projections 176 as shown, similar to the spline projections126, include one flat side and one curved side opposite the flat side.In some embodiments, the contoured profiles 174 may correspond (e.g.,form fit) to the interior profiles 118 of the channels 94, 102. Infurther embodiments, the contoured profile 174 may be complementary inshape to only a portion(s) of the shape of the interior profiles 118 ofthe spline 54. In other embodiments, the contoured profiles 174 may beentirely complementary in shape to the interior profiles 118 of thespline 54. In other words, the contoured profiles 174 may fully occupythe space provided by the recesses 98, 106 of the spline 54 with no voidspace. However, some gaps between the contoured profiles 174 and theinterior profiles 118 may exist due to manufacturing tolerances orassembly clearances but the general shapes of the interior profiles 118and contoured profiles do not vary. The first and second side edges 158,162 of the wall panels 42 have a thickness T that is greater than thethickness t of the mid-section 166 of the wall panels 42 when measuredin a common direction, i.e., the direction transverse to a direction ofextension, or width, of the wall panel 42 between the respective firstand second side edges 158, 162.

As discussed earlier, the wall panels 42 can span along the side walls26, 30, and front wall 34 of the trailer 10, or a wall panel 42 can spanthe entire length of one of the side walls 26, 30, or front wall 34 ofthe trailer 10. As such, the length between the first and second sideedges 158, 162 of the wall panels 42 can vary significantly, along withthe resulting aspect ratio of length to width. The thicknesses T, t mayalso vary as needed, based on construction material and strengthrequirements. In some embodiments, the first and second side edges 158,162 of the wall panels 42 may be reinforced with a coating. In someembodiments, the wall panels 42 may be made out of a composite material.In further embodiments, the wall panels 42 may be made out of a sheetmetal material such as aluminum.

FIG. 14 illustrates an alternate protrusion 177 for the first and secondside edges 158, 162 of the wall panels 42 according to the precedingdescription. The protrusion 177 is similar to the protrusion 170, withlike features being represented by like reference numerals. However, theprotrusion 177 of FIG. 14 further includes an additional concavity 178.The concavity 178 extends the entire length of the first and second sideedges 158, 162. The concavity 178 provides a volume and a surface for anadhesive to be applied between the spline 54 and the respective sideedges 158, 162. The adhesive may be applied along the surface of theconcavity 178 to bond the first and second side edges 158, 162 to thefirst and second channels 94,102 of the spline 54, respectively.

To assemble one of the spline joints 58 according to the presentdisclosure, the spline 54 is installed axially or lengthwise onto thetwo side edges 158, 162 of respective wall panels 42 being joined.Although reference is made directly to the spline 54 in the discussionof the assembly, it will be appreciated that the discussion also appliesto splines of any number of alternate constructions, such as splines130, 140. Before the spline 54 is installed, a first side edge 158 of arespective first wall panel 42 is positioned parallel to a second sideedge 162 of a respective second wall panel 42. The first side edge 158and the second side edge 162 are positionally fixed relative to eachother to define a space therebetween, which space corresponds directlyto the spacing between the channels 94, 102 of the spline 54. Next, thespline 54 is arranged such that the first channel 94 is positioned aboveand aligned with the first side edge 158 of the first wall panel 42, andthe second channel 102 is positioned above and aligned with the secondside edge 162 of the second wall panel 42. The spline 54 is then movedaxially in a direction parallel to its lengthwise direction into thespace between the two wall panels 42 such that the contoured profiles174 of the first and second side edges 158, 162 align with and slideinto engagement with the interior profiles 118 of the first and secondchannels 94, 102 of the spline 54. In some constructions, the splinejoints 58 are established with the wall panels 42 in their finalposition within the trailer 10, in which case the spline 54 is installedparallel to the trailer height H direction. During lengthwiseinstallation of the spline 54, the projections 126 on the interiorprofiles 118 of the first and second channels 94, 102 are aligned withand received by complementary recesses formed in the protrusions 170along the first and second side edges 158, 162. Furthermore, theprojections 176 on the contoured profiles 174 of the first and secondside edges 158, 162 are installed to be positioned directly alongsidethe projections 126. Finally, the spline 54 is slid axially furtheralong the contoured profiles 174 of the first and second protrusions 170to occupy an entire lengthwise extent of the space therebetween, or amajority thereof. The first wall panel 42 is mechanically secured to thesecond wall panel 42 immediately upon installation of the spline 54. Inthe illustrated embodiment, the contoured profile 174 of the first wallpanel 42 is entirely complementary to the first interior profile 118 ofthe first channel 94 and the contoured profile 174 of the second wallpanel 42 is entirely complementary to the interior profile 118 of thesecond channel 102, with the exception of assembly clearances that mayexist between the interior profiles of the first and second channels 94,012 and the contoured profiles 174 of the first and second contouredprofiles. Multiple spline joints 58 can then be assembled around theside walls 26, 30, and front wall 34 of the trailer 10 in a similarmanner to connect multiple wall panels 42 together. In someconstructions, every joint between adjacent pairs of wall panels 42throughout the entire trailer 10 is made by a spline joint 58 asdescribed herein.

As mentioned above, in some embodiments, the first and second side edges158, 162 of the wall panels 42 include a concavity 178 in the contouredprofile 174. When the spline joint 58 is assembled, the sides 122C ofthe interior profiles 118 of respective first and second channels 94,102 close the concavity 178. Once the first wall panel 42 has beensecured to the second wall panel 42, adhesive can be applied to theconcavities 178 on both the contoured profiles 174. The adhesive fillsthe concavities 178 for the entire length of the spline 54, or portionsthereof, to bond the surface of the concavity 178 with the sides 122A-Dof the interior profiles 118. The interior profiles 118 are completelyfilled and have no voids, although in this construction the protrusions174 along with the adhesive cooperatively fill the interior profiles118.

It should be noted that each of the protrusions 170 on the first andsecond side edges 158, 162 cannot be forced in a direction perpendicularto the length L1 of the spline 54, 130, 140 into the respective firstand second channels 94, 102 of the spline 54, 130, 140 in order to formthe spline joint 58 therebetween. In other words, the spline joints 58are not capable of being established by snapping or clicking into placevia elastic deformation of one or both mating components, and theprotrusions 170 will only fit into respective first and second channels94, 102 if the spline 54, 130, 140 is slid axially onto the first andsecond side edges 158, 162 of the wall panels 42.

FIG. 15 illustrates a spline joint 58 including a spline 54 without thecentral channel 134. The spline joint 58 includes a first side edge 158of a first wall panel 42 received within a first channel 94 and a secondside edge 162 of a second wall panel 42 received within a second channel102. FIG. 16 illustrates a spline joint 58 including a spline 130 withthe central channel 134. The spline joint 58 also includes a first sideedge 158 of a first wall panel 42 received within a first channel 94 anda second side edge 162 of a second wall panel 42 received within asecond channel 102.

As discussed earlier, the wall panels 42 of the trailers 10 may span ina multitude of ways around the side walls 26, 30, and front wall 34 ofthe trailer 10. For example, a spline joint 130 may join two wall panels42 on the first side wall 26 or the second side wall 30 of the trailer10 (FIG. 21 ) or a spline joint 130 may join two wall panels 42 on thefront wall 34 of the trailer 10 (FIG. 22 ). As such, the spline joints58 may be spaced around the side walls 26, 30, and front wall 34 of thetrailer 10 in a variety of ways. In addition, the side walls 26, 30, andfront wall 34 of the trailer 10 may meet in different ways to formdifferent kinds of corners (e.g., beveled 182, square 186, rounded 190,etc.). For example, as shown in FIG. 17 , a spline joint 58 including aspline 130 with the central channel 134 may be positioned on either thefirst or second side wall 26, 30 of the trailer 10 next to a beveledcorner 182 connecting a wall panel 42 on the front wall 34 to a wallpanel 42 on one of the side walls 26, 30. With reference to FIG. 18 , aspline joint 58 including a spine 130 may be positioned on a beveledcorner 182 connecting a wall panel 42 on the front wall 34 to a wallpanel 42 on one of the side walls 26, 30. Another example of a splinejoint 58 with a spline 130, as shown in FIG. 19 , may be positioned oneither the first or second side wall 26, 30 of the trailer 10 next to asquare corner 186 connecting a wall panel 42 on one of the side walls26, 30 to a wall panel 42 on the front wall 34. A further example, asshown in FIG. 20 , a spline joint 58 including the spline 130 with thecentral channel 134 may be positioned on either the first or secondsidewalls 26, 30 of the trailer 10 next to a rounded corner 190connecting a wall panel 42 on one of the side walls 26, 30 to a wallpanel 42 on the front wall 34. Although FIGS. 17-22 illustrate splinejoints 58 including the spline 130 of FIGS. 7 and 8 and no concavities178, any or all of these joints can also be made with other embodimentsdisclosed herein, or various feature combinations thereof (e.g., with orwithout the central channel 134 and with or without the concavities 178in any particular combination).

FIG. 23 illustrates the interior 22 of the trailer 10 with all the wallpanels 42 secured. The spline joints 58 are spaced around the first sidewall 26, the second side wall 30, and the front wall 34. The splines 140of the spline joints 58 all include logistic slots 142 that areconfigured to support fastening of additional structures inside theinterior 22 of the trailer 10. In other embodiments, only selectedsplines 140, or none of the spline 140, include logistic slots 142.

In some embodiments, the spline 54, 130, 140 of the spline joint 58 doesnot extend the entire length between the top edge 150 and bottom edge154 of the first and second wall panels 42. The spline 54, 130, 140 mayonly extend partially between the top and bottom edges 150, 154 of thefirst and second wall panels 42 to allow space for additional fasteningmeans above and below the spline joint 58. In further embodiments, thespline 54, 130, 140 may extend further than the first and second wallpanels 42 to establish direct or indirect engagement with the top andbottom rails 78, 82.

Various features and advantages of the invention are set forth in thefollowing claims.

What is claimed is:
 1. A container defining a cargo receiving interiordefined by a plurality of panels, the container comprising: a firstpanel having a first edge, the first edge having a first protrusion witha first contoured profile, the first contoured profile having at leastone projection; a second panel having a second edge, the second edgehaving a second protrusion with a second contoured profile, thecontoured profile having at least one projection; and a spline includinga first channel that defines a rectangular recess with an interiorprofile at least partially closed on four sides, and a second channelseparate from the first channel that defines a rectangular recess withan interior profile at least partially closed on four sides, wherein thefirst channel of the spline receives the first protrusion of the firstpanel such that the first contoured profile contacts all four sides ofthe rectangular recess of the first channel, and wherein the secondchannel of the spline receives the second protrusion of the second panelsuch that the second contoured profile contacts all four sides of therectangular recess of the second channel.
 2. The container of claim 1,wherein the first panel further includes a mid-section extending fromthe first edge and the second panel further includes a mid-sectionextending from the second edge, wherein the first edge has a greaterthickness than the thickness of the mid-section of the first panel andthe second edge has a greater thickness than the thickness of themid-section of the second panel.
 3. The container of claim 1, whereinthe rectangular recess of each of the first and second channels includesa male projection having both a flat side and a curved side opposite theflat side.
 4. The container of claim 1, wherein the first and secondprotrusions of the first and second edges of the first and second panelsare offset inward toward an interior of the container from a plane thatis defined by an interior surface of each of the first and secondpanels.
 5. The container of claim 1, wherein the first contoured profileextends an entire length of the first edge from a top edge of the firstpanel to a bottom edge of the first panel, and wherein the secondcontoured profile extends an entire length of the second edge from a topedge of the second panel to a bottom edge of the second panel.
 6. Thecontainer of claim 1, wherein the first and second channels of thespline open in opposite directions.
 7. The container of claim 6, whereinthe first and second channels of the spline are symmetrical to eachother about a plane that extends through the spline.
 8. The container ofclaim 1, wherein the spline further includes a central channelpositioned between the first channel and the second channel.
 9. Thecontainer of claim 8, wherein the spline further includes slots throughan interior wall of the central channel, the interior wall facing aninterior of the container.
 10. A container defining a cargo receivinginterior defined by a plurality of panels, the container comprising: afirst panel having a first edge, the first edge having a firstprotrusion with a first contoured profile, the first contoured profilehaving at least one projection; a second panel having a second edge, thesecond edge having a second protrusion with a second contoured profile,the contoured profile having at least one projection; and a splineincluding first and second separate channels, the channels definingrespective interior profiles, wherein the first channel receives thefirst protrusion of the first panel such that the first contouredprofile is complementary to a portion of the interior profile of thefirst channel, and wherein the second channel receives the secondprotrusion of the second panel such that the second contoured profile iscomplementary to a portion of the interior profile of the secondchannel, wherein the interior profiles of the first and second channelsinclude respective male projections extending into the respective firstand second channels, each male projection having both a flat side and acurved side opposite the flat side.
 11. The container of claim 10,wherein the first panel further includes a mid-section extending fromthe first edge and the second panel further includes a mid-sectionextending from the second edge, wherein the first edge has a greaterthickness than the thickness of the mid-section of the first panel andthe second edge has a greater thickness than the thickness of themid-section of the second panel.
 12. The container of claim 10, whereineach of the first and second channels of the spline defines arectangular recess at least partially closed on four sides.
 13. Thecontainer of claim 10, wherein the first and second protrusions of thefirst and second edges of the first and second panels are offset inwardtoward an interior of the container from a plane that is defined by aninterior surface of each of the first and second panels.
 14. Thecontainer of claim 10, wherein the first contoured profile extends anentire length of the first edge from a top edge of the first panel to abottom edge of the first panel, and wherein the second contoured profileextends an entire length of the second edge from a top edge of thesecond panel to a bottom edge of the second panel.
 15. The container ofclaim 10, wherein the first and second channels of the spline open inopposite directions.
 16. The container of claim 15, wherein the firstand second channels of the spline are symmetrical to each other about aplane that extends through the spline.
 17. The container of claim 10,wherein the spline further includes a central channel positioned betweenthe first channel and the second channel.
 18. The container of claim 17,wherein the spline further includes slots through an interior wall ofthe central channel, the interior wall facing an interior of thecontainer.
 19. A container defining a cargo receiving interior definedby a plurality of panels, the container comprising: a first panel havinga first edge, the first edge having a first protrusion with a firstcontoured profile, the first contoured profile having at least oneprojection, wherein the first panel further includes a mid-sectionextending from the first edge; a second panel having a second edge, thesecond edge having a second protrusion with a second contoured profile,the contoured profile having at least one projection, wherein the secondpanel further includes a mid-section extending from the second edge; anda spline including first and second separate channels, the channelsdefining respective interior profiles, wherein the first channelreceives the first protrusion of the first panel, and wherein the secondchannel receives the second protrusion of the second panel, wherein thefirst channel has an opening that opens in a direction perpendicular tothe mid-section of the first panel, and the second channel has anopening that opens in a direction perpendicular to the mid-section ofthe second panel, wherein the first protrusion of the first panel isoversized with respect to the opening of the first channel to precludepassage of the first protrusion through the opening of the firstchannel, and the second protrusion of the second panel is oversized withrespect to the opening of the second channel to preclude passage of thesecond protrusion through the opening of the second channel.
 20. Thecontainer of claim 19, wherein each of the first and second channels ofthe spline includes a male projection having both a flat side and acurved side opposite the flat side.
 21. The container of claim 19,wherein each of the first and second channels of the spline defines arectangular recess at least partially closed on four sides, wherein thefirst channel of the spline receives the first protrusion of the firstpanel such that the first contoured profile contacts all four sides ofthe rectangular recess of the first channel, and wherein the secondchannel of the spline receives the second protrusion of the second panelsuch that the second contoured profile contacts all four sides of therectangular recess of the second channel.
 22. The container of claim 19,wherein the first and second protrusions of the first and second edgesof the first and second panels are offset inward toward an interior ofthe container from a plane that is defined by an interior surface ofeach of the first and second panels.
 23. The container of claim 19,wherein the first contoured profile extends an entire length of thefirst edge from a top edge of the first panel to a bottom edge of thefirst panel, and wherein the second contoured profile extends an entirelength of the second edge from a top edge of the second panel to abottom edge of the second panel.
 24. The container of claim 19, whereinthe first and second channels of the spline open in opposite directions.25. The container of claim 24, wherein the first and second channels ofthe spline are symmetrical to each other about a plane that extendsthrough the spline.
 26. The container of claim 19, wherein the splinefurther includes a central channel positioned between the first channeland the second channel.
 27. The container of claim 26, wherein thespline further includes slots through an interior wall of the centralchannel, the interior wall facing an interior of the container.